• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 하계학술대회 논문집 Vol.3 No.2
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• pp.756-759
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• 2002

Nanoparticles of titanium dioxide$(TiO_2)$ were prepared by photochemical synthesis. Surface structure, morphology and particle size of $TiO_2$ thin films were investigated by UV-VIS spectrophotometer, scanning electron microscopy(SEM) and transmission electron microscopy(TEM). All process was prepared at room temperature. The absorption peak of the films was showed at 360nm and $TiO_2$ nanopaticle size was observed at about 20~30nm. Electron diffraction ring patterns of $TiO_2$ nanoparticles and crystallographic spacing were observed by TEM. As a result, crystallographic spacing was about 3.6A in HR-TEM micrographs.

• 대한화장품학회:학술대회논문집
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• 대한화장품학회 2003년도 IFSCC Conference Proceeding Book I
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• pp.568-569
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• 2003

Functional cosmetic ingredients such as L-ascorbic acid, retinoic acid, indole-3-acetic acid, salicylic acid, acidic dye(indigo carmine) are intercalatively encapsulated by skin-friendly metal hydroxides and oxides matrices. Such functional organic-inorganic nanohybrids are realized via chemical coprecipitation and surface coating reactions. The hetero-structural nature of these nanohybrids, their particle morphology and textural characterizations are mainly discussed on the basis of powder X-ray diffraction, electron microscopies, and high performance liquid chromatographic analyses. The cosmetic ingredients encapsulated in inorganics show greatly improved storage stability, sustained releasing property as well as higher transdermal transfer efficiency.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 1998년도 제27회 춘계학술대회
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• pp.314-320
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• 1998

Wear debris morphology is closely related to the wear mode and mechanism occured. Image recognition of wear debris is, therefore, a powerful tool in wear monitoring. But it has usually required expert's experience and the results could be too subjective. Development of automatic tools for wear debris recognition is needed to solve this problem. In this work, an algorithm for automatic wear debris recognition was suggested and implemented by PC base software. The presented method defined a characteristic 3-dimensional feature space where typical types of wear debris were separately located by the knowledge-based system and compared the similarity of object wear debris concerned. The 3-dimensional feature space was obtained from multiple feature vectors by using a multi-dimensional scaling technique. The results showed that the presented automatic wear debris recognition was satisfactory in many cases application.

• 한국결정성장학회지
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• 제13권2호
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• pp.63-67
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• 2003

Synthesis of $PbLaTiO_{3}$ : Mn powders containing La and Mn was carried out using $PbO,\;TiO_{2},\;La_{2}O_{3}\;and\;MnO_{2}$ as starting materials by hydrothermal method. In the synthesis of single phase $PbLaTiO_{3}$ : Mn powder containing La and Mn, the optimal x value corresponding to La substitution was 0.01 which corresponds to $0.99(Pb_{1-x}La_{2x/3}TiO_{3})+0.01MnO_{2}$. The optimal conditions for the preparation of the powder synthesis were 8 M-KOH solvent of hydrothermal solvent, $270^{\circ}C$ of reaction temperature and 24 hrs of run time. It was found that the synthesized powders had spherical morphology with average particle size of 70 nm and specific surface area of $5.5\;m^{2}/g$.

• 한국결정학회지
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• 제11권1호
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• pp.52-57
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• 2000

Hydrothermal synthesis of find CeO₂ powder has been investigated. Synthesis was performed with Ce(NO₃)₃·6H₂O, in ethanol and water solution. Mineralizer were NH₄OH and KOH and reaction for the powder synthesis has performed at 130℃. The morphology of CeO₂ was nearly spherical in using NH₄OH and cubic form in KOH. Particle size increased with addition of NH₄OH. Ethanol solution was effective to reduced the agglomeration.

• 한국세라믹학회지
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• 제30권7호
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• pp.543-548
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• 1993

Stability and formation of Pb(Mg1/3Nb2/3)O3 (PMN) phase synthesized in Li2SO4-Na2SO4 molten salts have been investigated. And powder characteristics of PMN have been studied with a variation of processing parameters such as temperature, time, amount of the salts, and excess PbO. More ratio of Li2SO4 to Na2SO4 influences the percentage of perovskite phase due to the difference of the eutectic point of the salts, but does not influence the powder characteristics. The shape of PMN particles shows faceted morphology with bimodal distribution consisting with large and submicron parts. Particle size of PMN increased greatly with increasing soaking time or amount of salts rather than temperature. The addition of excess PbO resulted in round PMN crystallites without submicron particles. These results are discussed by XRD, SEM and thermal analyses.

• 한국결정성장학회지
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• 제6권2호
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• pp.254-262
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• 1996

수열합성법을 이용하여 $1~3\;\mu\textrm{m}$의 입자 크기를 갖는 균일한 $Pb(Zr_{0.52}Ti_{0.48})O_{3}$ (PZT)분말을 제조하였다. 출발물질의 종류에 따라 반응조건이 다소 차이를 보였지만, 일반적으로 10 M의 KOH를 광화제로 사용하여, $180^{\circ}C$ 이상에서 2시간 동안 반응시켜 PZT 분말을 합성 할 수 있었다. 또한, 광화제의 농도, 수열반응 온도, 그리고 반응시간이 증가할수록 균일상의 분말이 형성됨을 보였다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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• pp.1514-1517
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• 2005

The $(Y,Gd)BO_3:Eu^{3+}$ phosphor was made by coprecipitation method. The precipitated powders were amorphous. The value of pH in the process of coprecipitation was critical for the luminescence of phosphors. The particle size and morphology were influenced by pH value. The lower calcination temperature and hydrothermal synthesis leads to the distortion of lattices. The distorted lattices changed the symmetry of $Eu^{3+}$ site. The broken inversion symmetry in the distorted lattice caused the increased emission of $^5D_0{\rightarrow}^7D_2$ transition.

• Bulletin of the Korean Chemical Society
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• 제35권8호
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• pp.2251-2256
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• 2014

We have successfully decorated reduced graphene oxide (RGO) with silver nanoparticles (AgNPs) by microwaving silver alkylcarbamate for 13 seconds using 1-amino-4-methylpiperazine. Uniform AgNPs (20-40 nm) were effectively prepared, and 1-amino-4-methylpiperazine acted as a reaction medium, reducing agent, and stabilizer. Particle size and morphology were correlated with the silver alkylcarbamate concentration and microwave time. The graphene/AgNPs composites were characterized by Raman, X-ray diffraction, and scanning electron microscopy to confirm that the AgNPs were uniformly decorated onto the graphene. Measurements of the transparent conductive property at room temperature indicated that these graphene/AgNPs nanosheets with 55.45% transmittance were electrically continuous with a sheet resistance of approximately $43{\Omega}/{\Box}$.

• 한국식물병리학회지
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• 제14권3호
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• pp.223-228
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• 1998

Turnip mosaic virus)TuMV-Ca) was isolated from a Chinese cabbage showing severe mosaic and black necrotic spots symptoms in Korea. The virus was identified as a strain of TuMV by its host range test, particle morphology, serology, double stranded RNA analysis. For detection of the virus, reverse transcription and polymerase chain reaction(RT-PCR) was performed with a set of 18-mer TuMV-specific primers to amplify a 876 bp DNA fragment The virus was rapidly detected from total nucleic acids of virus infected tissues as well as native viral RNA of purified virion particles by RT-PCR. Detection limit of the viral RNA by RT-PCR was 10 fg.